The US will have no grounds to criticize anyone for human rights abuses as it seeks to reconcile with an authoritarian state. Saudi Arabia has utterly devastated Yemen and has committed more violations of human rights than anyone can count. For the sake of pragmatism, accountability and justice for those who have suffered under Riyadh's autocratic rule will be entirely ignored, and the kingdom will have the weapons to continue unabated.
Iran is the biggest threat to peace in the Middle East, and it's in everyone's best interests to support Saudi Arabia as a counterweight. Saudi Arabia has intercepted Houthi missiles with US arms, something they wouldn't have in their possession if the anti-Saudi crowd got their way. Rapprochement with Saudi Arabia makes sound foreign policy sense and will help ease the threat of the region's worst human rights abuser: Iran.